Means for pre-heating air for introduction into incinerators



L. M. FORD Aug. 13, 1968 MEANS FOR FEE-HEATING AIR FOR INTRODUCTION INTO INCINERATORS Filed June 21, 1967 '2 Sheets-Sheet 1 INVENTOR.

LEWIS 'M FORD Aug. 13, 1968 FORD 3,396,683

MEANS FOR PRE-HEATING AIR FOR INTRODUCTION INTO INCINERATORS Filed June 21, 1967 2 Sheets-Sheet 2 F/GZ INVENTOR.

LEW/S M. FORD United States Patent 3,396,683 MEANS FOR PRE-HEATING AIR FOR INTRO- DUCTIGN INTO IYCINERATORS Lewis M. Ford, Memphis, Tenn., assignor to Steelcraft Corporation, Memphis, Tenn., a corporation of Tennessee Filed June 21, 1967, Ser. No. 647,758 Claims. (Cl. 110-18) ABSTRACT OF THE DISCLOSURE An apparatus for withdrawing preliminarily heated air from the structure of an incinerator, introducing the same for additional heating through a duct exposed to the heat of the interior of the incinerator into a blower for subsequent delivery to the combustion chamber of the incinerator.

BACKGROUND OF THE INVENTION Field of the inveizti0n.-The present invention relates to the elimination of the problems in continuing the proper firing of incinerators and to the provision of substantially self-contained forced draft means for furnishing pre-heated air to assist in the combustion of the materials in the combustion chamber of the incinerator.

Description of the prior urn-There have been prior devices for increasing the efficiency of combustion within an incinerator, but these prior devices have been restricted to the utilization of externally positioned heated means with atmospheric air conducted therethrough and injected therefrom into the combustion area of the incinerator. These prior devices have additionally been provided with baffies, plates and similar means for defleeting and directing the pre-heated air into the combustion area of an incinerator.

None of the known prior art provides for utilizing the heat of the incinerator for pre-heating the air of combustion.

A search of the prior art disclosed the following references:

1,496,900, W. F. Mitchell, June 10, 1924; 2,760,451, G. V. Thompson, Aug. 28, 1956; 2,850,991, G. V. Thompson, Sept. 9, 1958; 3,267,890, R. E. Zinn et al., Aug. 23, 1966.

Summary of the invention-The present invention is directed toward the furnishing of pre-heated air in connection with combustion to and through the grates of an incinerator and is primarily concerned with a system in which external atmospheric air is admitted between the outer skin and inner liner of an incinerator to effect dissipating of the external heat of the incinerator and thus the air absorbing heat from the internal heat of the incinerator, with a duct mounted within the incinerator to receive the full heat of the incinerator for the heating of the air contents thereof, the duct being connected to the space between the outer skin and inner liner of the incinerator so as to receive air pre-heated in that area and to withdraw the same into the duct for exposure to the full internal heat of the incinerator, the duct being connected to a blower fan and communicated with the interior of the incinerators so as to deliver the pre-heated air to the incinerator for facilitating the burning of the refuse therein.

0bjects.-The principal object of the present invention is to provide a system for delivering pre-heated air utilizing primarily pre-heated air of an incinerator structure together with exposure of that air in a container mounted within the incinerator heat area for further heating and delivery thence to the grate area of the device.

3,395,683 Patented Aug. 13, 1968 ice A further object of the invention is to provide such a device which includes an elongated duct mounted interiorly of the incinerator and exposed to the internal heat of the incinerator which communicates with the air preheated between the outer skin of the incinerator and the inner liner so as to receive withdrawal of such preheated air for further heating and which is communicated at its opposite end to a blower fan for delivery to the incinerator combustion chamber of the heated air.

A further object of the invention is to provide an incinerator in which the outer skin is spaced outwardly from the inner liner and the lower skirt of the outer skin is spaced upwardly from the lower edge of the inner liner so as to permit a peripheral introduction of atmospheric air into the space between the outer skin and the inner liner.

A further object of the invention provides an incinerator in which such an inner liner is provided with a plurality of spaced inlets communicating the atmospheric air into the interior of the combustion chamber.

Description of the drawings.-The means by which the foregoing and other objects of the present invention are accomplished, and the manner of their accomplishment, will be readily understood upon reference to the accompanying drawings, in which:

FIG. 1 is a plan view of an incinerator having the present invention incorporated therein.

FIG. 2 is a vertical view partly in elevation, and partly in cross section, as taken on the line II-II of FIG. 1.

FIG. 3 is an enlarged fragmentary cross sectional view of the device of FIG. 1 as taken on the line III-III of FIG. 1.

FIG. 4 is an enlarged fragmentary cross-sectional view of the device of FIG. 1 as taken on the line IVIV of FIG. 1.

Description of the preferred embodiment-Referring now to the accompanying drawings in which the various parts are indicated by numerals, the present invention includes an elongated air duct 11, substantially rectangular in cross section provided with an upper housing 13 and a lower housing 15 interconnected as at the flanged portion 17 by bolts or similar fasteners to form the substantially unitary duct 11. The duct 11 is disposed within the combustion chamber 19 of an incinerator 21 in spaced adjacency and substantial parallel alinement with the inner liner 23 of the incinerator, which liner is seated upon the floor mounting of the incinerator. The upper housing 13 of duct 11 is provided with an intake pipe 25 attached at one of its ends to upper housing 13 adjacent the top thereof, and at its opposite end to the inner liner 23. The intake pipe 25 opens into the duct 11 and through liner 23 and provides means of communication between the inner chamber 27 to the upper housing 13 and the air chamber 29 of the incinerator 21 formed by the inner liner 23 and the outer skin 31 of the incinerator 21.

The lower housing 15 of the air duct 11 is provided with an air discharge pipe 33 attached to and communicating at one of its ends with the lower housing 15 of duct 11 adjacent the bottom thereof and at its opposite end being attached to and communicating through the inner liner 23 to provide air communication between the inner chamber 35 of the lower housing 15 of the air duct 11 and a forced draft fan 36 positioned external the incinerator 21. Pipe 33 preferably extends outwardly beneath the skirt of the outer skin of the incinerator.

The incinerator 21, being preferably of substantially frustoconical design, is provided with a dome 37 resting thereupon at its upper extremity and attached thereto as by the brace member 39. The dome 37 is provided with cap means 41 rigidly aflixed thereto having an offset throat portion 43 in communication therewith to direct the smoke and other byproducts of combustion in the combustion chamber 19 of the incinerator 21 through the throat portion 43 into the smoke duct 45 and there- 'beyond to a scrubber 47 whereby the air pollutants and similar materials are combined with water to form a substantially sludgelike composition which may be transported to and deposited Within a suitable container therefor.

The outer skin 31 of the incinerator 21, substantially alined in parallelism with the inner liner 23 is provided with a plurality of peripherally spaced support members 49 attached to the lowermost inner portio of the outer skin 31 extending downwardly therefrom into subtsantially rigid attachment with the incinerator floor 51 to maintain the peripheral lower edge portion 53 thereof in spaced relation above the incinerator floor 51 to form a substantially circumferential air ingress means 55 permitting the external atmosphere to enter therethrough into the air chamber 29 of the incinerator 21, formed between outer skin 31 and inner liner 23 which are spaced apart.

Floor 51 of incinerator 21 is provided with grate means 57 located substantially centrally of the incinerator and open for the flow of air therethrough toward the refuse and material being burned in the incinerator. Connected to grate 57 is an air pipe 53 which is communicated with and receives the discharge from blower fan 36 so as to provide delivery of the heated air withdrawn through duct 11 to the grate and thence into the interior of the incinerator for enhancing the burning action therein. It can be seen that in this manner fan 36 is enabled to deliver the pre-heated air, comprising air first heated in the air chamber surrounding the incinerator and thence additionally heated in the duct 11, directly into the grate 57 so as to further forward the burning of the contents of the incinerator and to eliminate difliculties in combustion therein.

Fan 36 is driven by drive means 61 preferably from a suitable source of power (not shown) connected to the drive means 61. A plurality of spaced radially alined hollow tubes 63 are substantially horizontally disposed with relation to the incinerator floor 51, rigidly aflixed to the inner liner 23 somewhat above the incinerator floor 51 and below the peripheral edge of outer skin 31, communicating through the inner liner 23 between the atmosphere external the incinerator 21 and the combustion chamber 19 within the incinerator 21 to allow a desired amount of air from the atmosphere to enter the combustion chamber 19 in order to support combustion therein.

It will thus be readily seen and understood upon reference to the accompanying drawings and the foregoing description of the preferred embodiment of the present invention that the pre-heated air is ejected from the grates 57 and is delivered into the combustion chamber enhancing the combustion therein. The ensuing heat of combustion of the material in the combustion chamber 19 is transmitted to the inner liner 23 therearound increasing the temperature thereof. The substantially cooler air entering the air chamber 29 through the air ingress means 55 is warmed by the inner liner 23 and pursuant to this warming rises upwardly in the air chamber 29. When the forced draft fan 36 is energized, the warmer air moving upwardly through the chamber 29 is urged through the intake pipe 25 into the duct 11 to replace the air removed therefrom by the forced draft fan 36. The heated air entering the inner chamber 27 of the upper housing 13 of the duct 11 is further urged downwardly into the chamber 35 of the lower housing of the duct 11, acquiring additional heat in its passage downwardly therethrough from duct 11 fully exposed to the internal heat of the incinerator. The pre-heated air 4 in the chamber 35 of the lower housing 15 is urged by the forced draft fan 36 away from the duct 11 through the discharge pipe 33 and the forced draft fan 36 into and through the intake means 59 wherein it is injected into the grates 57 to provide a substantially pre-heated airflow for a more complete and effiicient firing of the material in the combustion chamber 19 of the incinerator 21.

The byproducts of the combustion within the combustion chamber 19 of the incinerator 21 rise upwardly therein into the cap 41 of the dome 37 and outwardly therefrom through the throat portion 43 into the smoke duct 45. The smoke and particled matter combined therewith is drawn from the smoke duct 45 into the scrubber 47 where the combinaiton of smoke and particles is washed allowing the cleaned gaseous product to re-enter the atmosphere and the water laden particles to drop as by gravity to the bottom of the scrubber 47 and thence to a suitable container or sump.

I claim:

1. Means for delivering pre-heated air to the combustion chamber of an incinerator in which (A) said incinerator comprises (1) a floor forming the base of the incinerator,

(2) an inner liner (a) seated on said floor,

(b) extending upwardly therefrom, and

(c) comprising the interior of said incinerator exposed to the heat of combustion in said incinerator,

(3) an outer skin mounted to said incinerator substantially surrounding said inner liner,

(a) spaced outwardly from said inner liner, defining an air chamber between said outer skin and said inner liner embracing said inoinerator combustion chamber for dissipating combustion heat therefrom,

(b) means to provide access of the air of atmosphere to the air chamber between said skin and said liner,

(c) air conduit means communicating through said liner into said combustion chamber to receive air of atmosphere and introduce same to said combustion chamber,

(B) a hollow duct mounted within said combustion chamber and connected to said inner liner,

(1) adjacent its upper end in flow connection through said inner liner with the interior of said air chamber to receive air chamber contained air warmed by said incinerator,

(2) means leading from the lower part of said duct to discharge duct received air,

(3) said duct being exposed to the heat of combustion in said incinerator to further heat said warmed air in said duct,

(C) fan means (1) connected to said lower duct air discharging means for moving and discharging said heated warmed air from said duct,

(2) communicated with the interior of said combustion chamber and discharging upwardly into said combustion chamber,

whereby to deliver said heated warmed air as pre-heated air to enhance combustion in said combustion chamber.

2. Means in accordance with claim 1, in which the lower terminal edge of the outer skin is spaced upwardly from said floor peripherally around said outer skin.

3. Means in accordance with claim 1, in whidh said air conduit means comprise tubes projecting inwardly from said inner liner into the interior of said combustion chamher.

4. Means in accordance with claim 2, in which said air conduit means are positioned below the upwardly spaced edge of the outer skin.

5. Means in accordance with claim 1, in which means 5 6 communicating said blower fan with the interior of said 2,760,451 8/1956 Thompson 110 18 combustion chamber are located substantially centrally of 2,850,991 9/ 1958 Thompson l10l8 the floor of said combustion chamber. 3,267,890 8/ 1966 Zinn et a1 11018 References Cited 5 FOREIGN PATENTS UNITED STATES PATENTS 451316 3/1917 Sweden- 72,339 12/ 1867 Tiffany 12677 XR FREDERICK L. MATTESON, 111., Primary Examiner. 1,496,900 6/1924 Mitchell 11018 2,452,843 11/1948 Pelterie 110 7XR H-BRAMEYAssistamExaminer' 

